A tourist boat carrying close to 170 passengers capsized on Sunday close to the Colombian city of Medellin. Authorities believe that at least 6 people died and 16 are still missing.

Dramatic videos are circulating on social media showing El Almirante ferry rocking back and forth as people rushed to the roof while the boat was sinking in a matter of minutes.

The air force and firefighters are searching for survivors at the Guatape lake reservoir where the ferry sank. Survivors described to local media hearing a loud explosion before the boat ran out of power.

"We don't know what happened, 5 minutes after the departure everything was fine when we heard a loud explosion, ran out of power and watch how half of the boat was sinking. That's when all the people ran to the other side. Everyone was screaming and water started to flood on board. People who was on the upper level wouldn't let us go up. I took 2 kids and got ready to get out of there swimming.", a survivor told local media.

As water flooded on board, pressure built and people were sucked under by the sinking ship. One of the survivors told El Tiempo newspaper the crew never gave lifejackets to the passengers.

It is unclear what caused the accident but survivors told the press that the boat appeared to be overloaded.